Noise reduction means for air outlet devices



Jan. 21,1958 P. A. ARGENTIERI 2,820,406

noxsE REDUCTION MEANS FOR AIR OUTLET DEVICES,

Filed May 14, 1954 FIG. \I

mmvrozc NOISE REDUCTION MEANS FOR AlR OUTLET DEVICES Danbury, Conn., assignor to Connor Danbury, Conn., a corpora- Peter A. Argentieri,

Engineering Corporation, tion of New York This invention relates to improvements in an air outlet device or diffuser for air-conditioning systems, an example of such device being found in my co-pending application Serial No. 303,923, filed August 12, 1952, now Patent No. 2,745,509.

It is desirable to provide in devices of this character, and particularly when the air ducts employed are of relatively small diameter, means by which the noise conditions are materially reduced and to an extent where the noise is relatively negligible.

It is therefore one object of the present invention to provide an improved air outlet device of the character mentioned which is constructed and arranged in such the generation of objectionable noises upon the discharge further object of the invention is the provision of an outlet device of the above mentioned character having an inexpensive and readily-adjustable throttling means to prevent the formation of high velocity jets of large mass within the device and consequently minimizing vortex and impingement noises.

It is another object of the invention to provide a de vice for connection to the outlet of an air duct, which device shall be in the form of a casing or housing defining an air passage of sinuous form, said passage having an outlet arranged at an angle to the air flow through the sinuous passage, and adjacent to and partly extending around the outlet is arranged a vertical, arcuate baffle plate or wall of foraminous construction behind which is placed a sound-proofing material. By a construction as above described, a noise-reduction means of maximum efficiency is provided.

With the objects above set forth in view, 1 have devised the arrangement of parts hereinafter set forth and more particularly pointed out in the claims appended hereto.

In the accompanying drawing, wherein an illustrative embodiment of the invention is shown,

Fig. l is a vertical sectional view through an air outlet device embodying the features of the invention, and

Fig. 2 is a sectional view, taken substantially on the line 2-2 of Fig. 1, looking in the direction of the arrows.

An efiicient air outlet device should be provided with a throttling or controlling means for the air volume, and the present invention includes a perforated cylinder into which the air enters and in which a closure disc or diaphragm is axially adjustable for variable throttling effects. Referring to the drawing, indicates said perforated cylinder having a plurality of perforations 11, thus rendering the air distributing area of the cylinder foraminous. This cylinder may be either fixedly attached in the end wall 12 of the housing 13, or it might be axially adjustable through said wall if found desirable. The cylinder 10 is connected in the end of an air inlet duct so that the air passing through such duct will flow through the cylinder 10 and out through the perforations therein to enter the chamber 50 in the housing. The air-distributing duct United States Patent 0 2,820,406 Patented Jan. 21 1958 'ice in which the cylinder 10 is fitted is of conventional construction, generally located between the walls or in a suitable ceiling space. The housing 13, in the form shown, is of substantially rectangular shape, and the inner surfaces of its walls receive a layer of sound-absorb ing material 14 to minimize noise and vibration due to air impact. It will be observed that while the sound-ab sorbing material 14 surrounds the cylinder 10 it is spaced therefrom.

Mounted for adjustment within the cylinder 10 is a closure disk or diaphragm 15 which is axially slidable Within the cylinder to produce the desired throttling effect without generating high velocity solid streams and resultant erratic flow within the device. The diaphragm 15 is closely, but slidably fitted within the cylinder 10 and is provided with a sealing member 16. The outlet end of the cylinder 10 may be flared slightly as indicated at 17. The diaphragm is adjustable axially within the cylinder 10 to secure the desired throttling effects, by means of the rod or shaft 18 attached at one end to the diaphragm 15, and slidably guided through a sleeve 19 secured on a strut or post 20 extending across the housing 13. A bar 22, extending inwardly from the end wall 44 of the housing 13, is provided with a guide sleeve 24 through which the rod or shaft 18 is also slidable. At one end, the rod or shaft 18 is provided with a toothed rack 25 in mesh with a pinion 26 on the end of a vertical shaft 27, rotative in lugs 28 provided on the bar 22. The shaft 27 extends downwardly through a guide sleeve 29 and through the diffuser 30 and terminates in a knob 31 at the lower end of the diffuser and by which the shaft 27 is manually rotated to thereby move the rod 18 longitudinally and thus arrange the position of the disc or diaphragm 15 within the sleeve 10.

Contained within the housing sinuous air passage 32 provided in of perforations 33 so that the wall of said passage is in fact foraminous. Said foraminous wall has its outer surface covered by sound-absorbing material 34. The outlet for the passage 32 is indicated at 35 and the passage and said outlet is contracted or is of slot-like formation as best seen in Fig. 2. The inlet end 51 of the sinuous passage is located in the chamber 50, and said inlet may be slightly flared as shown in Fig. 1.

The outlet end 35 of the sinuous passage 32 communicates with a chamber 36 which is defined by a vertical, arcuately curved, semi-cylindrical bafie or deflecting wall 37 which is perforated as indicated at 38, or is foraminous. One of the walls of the chamber 36 is provided with the outlet opening 40 to which the diffuser 30 of known construction is connected, as clearly seen in Fig. l. Said Wall is lined around the opening 40 with sound-absorbing material 41. The opposite wall 42 of the chamber 36 is also lined with sound-absorbing material as indicated at 45. The latter lining of sound-absorbing material is spaced from the curved wall or baffle 37 so that the pockets 46 and 47 '(Fig. 2) are provided between the curved wall or' baffle 37 and the walls of the housing behind the same. The pockets 46 and 47 are lined with the sound-absorbing material 14. As an alternative, the sound-absorbing material might be directly attached to the outer face of the arcuate wall or bafile 37 rather than being spaced therefrom.

From the foregoing, be apparent. inder 10 will 13 is a serpentine or its wall with a plurality the operation of the device will Air entering through the perforated cylflow laterally through the holes in the same and enter into the chamber 50 of the housing. The air will then flow through the sinuous passage 32 passing through the diffuser 30 and into the room. The bafile or deflecting wall 37 limits the turbulence of the air stream and materially reduces the noise level of the device. the employment of a perforated semi-circular wall or for the air flow as would be secured plate, but by the use of a perforated Wall or bafile, the sound waves are permitted to pass through such wall or bathe and become absorbed by the sound-absorbing material located behind the baille.

Having described one embodiment of the invention, it is obvious that the same is not to be restricted thereto, but is broad enough to cover all structures coming within the scope of the annexed claims.

What I claim is:

l. A noise-reduction means for connection to the out let of an air duct comprising, a housing lined with soundabsorbing material, said housing having an inlet chamher into Which air enters, a sinuous passage leading from said chamber, a second chamber within the housing and spaced from the first chamber, the second chamber havpassage being located in the space between the chambers and having its outlet end in communication with the second chamber, the bottom of the second chamher being opening, a curved, perforated bathe wall extending from one side wall to the opposite side wall and from the bottom wall to the top Wall of the second chamber and arranged in the second chamber around the outlet opening, said wall being spaced from the outlet end of the sinuous passage, sounda disc slidable within said cylinder and throttle, a shaft attached to the disc, a rod extending vertically through the outlet opening in the second chamber and a coupling between said rod and the shaft whereby longitudinal movement of the shaft occurs when the rod rotated to thereby shift the position of the disc within the cylinder, the sound-absorbent material behind the curved perforated baffle Wall being spaced from said Wall whereby a pocket is formed between said well and said sound-absorbent material.

2. A noise reduction means for connection to the outlet of an air duct comprising, a housing divided into three chambers, one of said chambers being located at one end of the housing and having a well through which a pering having an outlet opening in one of its Walls disposed at right angles to the wall through which the perforated cylinder extends, a diflfuser connected to said outlet open the end chamber provided with the outlet opening, one of the ends of the sinuous passage being located adjacent to the lower wall of one of the end chambers and having opening in said let opening, said perforated w absorbing material contained 3. A noise-reduction means let of an air wall, a top outlet openin let opening, inlet and 0 wall, end

chamber and partially encircling said outwithin the housing.

all being backed by soundfor connection to the outduct comprising, a housing having a bottom Walls and side Walls, said housing the bottom wall of the housing,

the outlet opening from said passage being located in the outlet chamber and being situated closely adjacent to the top wall of the houssaid arcuate wall extending from one side wall to the opposite side Wall and from the top wall to the bottom Wall of the outlet chamber and the housing absorbent material in all the chambers thereof.

4. A noise-reduction means for connection to the outlet of an air duct comprising, a housing being lined with soundhaving an end wall, a perforated cylinder passing through said end wall sage being of the pass side facing t disaligned with respect age, the second ch a semi-circular, perforated ba he outlet of the forated bafile Wall extending amber being provided with the wall having its concave sinuous passage, said perfrom one side wall to the opposite side Wall and from the bottom wall to the top wall of the second chamber and spaced from the outlet partly encircling the outlet chamber, said perforated ba References Cited in the file of this patent UNITED STATES PATENTS and being arranged around of the sinuous passage and in the Wall of the second file wall being spaced from 

